I was searching around a bit, but I didn't come across anything with this problem--similar but not the same.

The issue is when there is 1/4 tank or less of gas in the car, after sitting at idle for a bit (ie. at a stop light) and I go to accelerate the RPMs drop to about 500 and I need to depress the accelerator at least half way or more to pick it back up. It wont stall but chugs along nice and slow until it catches up by its self or I give it more gas.

Everything is fine if there is more than 1/4 tank of gas. '04 MT, sparks and coils are almost due. The reason the sparks and coils arn't my #1 suspicion is because everything is fine on a full tank. However I am going to check my coils on Saturday anyway.

Anyone have better insight on this?

 

I had this exact issue with a Ford Probe once and it turned out to be an overheating fuel pump. Would only happen on a low tank as there wasn't enough fuel surrounding it to keep it cool. I replaced it and all was well.

Granted it wasn't an rx8 but it sound like the same issue. Perhaps a member with more fuel system experience on the 8 will chime in.

 

i have the same problem and i did the necessary tune up, my suspicion for me is either a bad cat or low compression. for you i would suggest you check the coils!! that can cause alot of problems. i also have an 04 and for us a compression test is a must!!!

do the tune up and let us know how she feels

 

Take a look at MazdaManiac's fuel pump 'starvation' issues thread. Very informative and may well be the culprit.

 

Thanks for the info on that, I didn't realize there was a thread explaining the fuel pump. I had read the one on BHR's site a while ago though. I guess I'm in luck too because they just released their entire mod for purchase.

So I guess I'm kind of at a fork in the road. Money is kinda tight at the moment and I can really only afford to either get the new pump or replace my plugs and coils. I'm leaning toward the pump right now because I'm not having any issues with the later. But then again, if my coils look completely shot I might have to go with those and hope for the best?

 

Ignition is certainly important, but if there's nothing to ignite .....

 

I think I'm going to opt for the compression test before I do anything. We've got our summer heat starting now and I get complete power loss from a 15 minute drive across town. It actually stalled out on me a couple blocks from my house.

It wasn't really noticeable before, but now that its actually hot out.. mannnnnn! Hopefully if it fails the test (which I'm pretty sure it will @ 144,000kms original) I won't get a run-around for a new engine...